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Specifying the unique key columns</TITLE>
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<A NAME="BHBIAHFH"></A><h1>Specifying the unique key columns</h1>
<A NAME="TI6211"></A><p>The Unique Key Columns box in the Specify Update Properties
dialog box specifies which columns PowerBuilder uses to identify a
row being updated. PowerBuilder uses the column or columns you specify
here as the key columns when generating the <b>WHERE</b> clause
to update the database (as described below):</p>
<br><img src="images/aacu03.gif">
<A NAME="TI6212"></A><p>The key columns you select here must uniquely identify a row
in the table. They can be the table's primary key, though
they don't have to be.</p>
<p><img src="images/note.gif" width=17 height=17 border=0 align="bottom" alt="Note"> <span class=shaded>Using the primary key</span> <A NAME="TI6213"></A>Clicking the Primary Key button cancels any changes in the
Unique Key Columns box and highlights the primary key for the updatable
table.</p>

